/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.runners.gaia.translation.functions;



import com.bff.gaia.unified.sdk.transforms.windowing.BoundedWindow;

import com.bff.gaia.unified.sdk.transforms.windowing.Window;

import com.bff.gaia.unified.sdk.transforms.windowing.WindowFn;

import com.bff.gaia.unified.sdk.util.WindowedValue;

import com.bff.gaia.api.common.functions.FlatMapFunction;

import com.bff.gaia.util.Collector;



import java.util.Collection;



/**

 * Gaia {@link FlatMapFunction} for implementing {@link

 * Window.Assign}.

 */

public class GaiaAssignWindows<T, W extends BoundedWindow>

    implements FlatMapFunction<WindowedValue<T>, WindowedValue<T>> {



  private final WindowFn<T, W> windowFn;



  public GaiaAssignWindows(WindowFn<T, W> windowFn) {

    this.windowFn = windowFn;

  }



  @Override

  public void flatMap(WindowedValue<T> input, Collector<WindowedValue<T>> collector)

      throws Exception {

    Collection<W> windows = windowFn.assignWindows(new GaiaAssignContext<>(windowFn, input));

    for (W window : windows) {

      collector.collect(

          WindowedValue.of(input.getValue(), input.getTimestamp(), window, input.getPane()));

    }

  }

}